I picked up a English Setter pup in March, the first few weeks Zeke the GSP would growl and bare his teeth but after a while things settled down. Well this weekend Zeke has started attacking my poor 9 month old pup and for no reason. Has him on the ground and biting him. The pup is in the submissive posture but Zeke keeps at him till I pull him off. I may need to find a home for the pup but would like to keep him. Zeke's too old to re-home, 8, and my kids would disown me. Any suggestions?

Sudden aggression could be a health issue. I would take this dog to the vet. Beyond that some dogs are just dog aggressive and difficult if not impossible to change. If this is the case, don't let them interact.

My shorthair doesn't care for pups, she likes to harass them for her pleasure but that's it. If she showed any real aggression towards if whoop her butt til she wanted to cuddle with them. She knows pups are part of the family and to get over it. Mine is 8 as well. Next time come down real hard on him and every time he shows any aggression at all tell them to be nice, in a real commanding voice. Mine got the picture.